diff --git a/include/common/standard.h b/include/common/standard.h
index 2645c44dd..535efa736 100644
--- a/include/common/standard.h
+++ b/include/common/standard.h
@@ -1202,7 +1202,7 @@ static inline unsigned char utf8_return_length(unsigned char code)
 static inline unsigned long long my_htonll(unsigned long long a)
 {
 #if defined(__x86_64__)
-	__asm__ volatile("bswap %0" : "=r"(a));
+	__asm__ volatile("bswap %0" : "=r"(a) : "0"(a));
 	return a;
 #else
 	union {